VERITAS Volume Manager 4.1 Administrator's Guide

Glossary
stripe
Glossary 435
other disk groups, which are used for backup
purposes only. It also contains disk records
that define all disk devices on the system.
root disk The disk containing the root file
system. This disk may be under VxVM
control.
root disk group A special private disk
group that always exists on the system. The
root disk group is named rootdg. Even
though rootdg is the default disk group, it
does not necessarily contain the root disk
unless this is under VxVM control.
root file system The initial file system
mounted as part of the UNIX kernel startup
sequence.
root partition The disk region on which
the root file system resides.
root volume The VxVM volume that
contains the root file system, if such a
volume is designated by the system
configuration.
rootability The ability to place the root file
system and the swap device under VxVM
control. The resulting volumes can then be
mirrored to provide redundancy and allow
recovery in the event of disk failure.
secondary path In active/passive disk
arrays, the paths to a disk other than the
primary path are called secondary paths. A
disk is supposed to be accessed only through
the primary path until it fails, after which
ownership of the disk is transferred to one of
the secondary paths. Also see path and
primary path.
sector A unit of size, which can vary
between systems. Sector size is set per
device (hard drive, CD-ROM, and so on).
Although all devices within a system are
usually configured to the same sector size for
interoperability, this is not always the case.
A sector is commonly 1024 bytes.
shared disk group A disk group in which
access to the disks is shared by multiple
hosts (also referred to as a cluster-shareable
disk group). Also see private disk group.
shared volume A volume that belongs to a
shared disk group and is open on more than
one node of a cluster at the same time.
shared VM disk A VM disk that belongs to
a shared disk group in a cluster.
slave node A node that is not designated as
the master node of a cluster.
slice The standard division of a logical disk
device. The terms partition and slice are
sometimes used synonymously.
spanning A layout technique that permits
a volume (and its file system or database)
that is too large to fit on a single disk to be
configured across multiple physical disks.
sparse plex A plex that is not as long as the
volume or that has holes (regions of the plex
that do not have a backing subdisk).
Storage Area Network (SAN) A
networking paradigm that provides easily
reconfigurable connectivity between any
subset of computers, disk storage and
interconnecting hardware such as switches,
hubs and bridges.
stripe A set of stripe units that occupy the
same positions across a series of columns.